The most remote (full size) four wheel drives in the solar system are, for the forseeable future, the three lunar roving vehicles (LRV) left on the surface of the moon by the Apollo 15 (above), 16 and 17 missions.
The Rovers were built by Boeing and were driven by four electric motors - one per wheel just like some of the earliest four wheel drives and as the US army is experimenting with in the RST-V. In this case the power was provided by batteries. The most severe design requirements were low weight (from 180kg depending on equipment), small folded size to fit on the LEM, and the ability to withstand extreme temperatures caused by the lack of an atmosphere on the moon.
Steering was by the front, the rear, or all four wheels.
Speed was 10-12km/h which was apparently
quite fast enough for serious off-road use in 1/6 G -
LRVs were fitted with seat belts and these were essential.
On the other hand, a wind shield was completely unnecessary.
- 4wd.sofcom.com/4WD.html
The last three Apollo moon missions had the use of LRVs:
Apollo 15, was launched on 26 July 1971,
landed on the moon on 30 July (Hadley Rille 26d05'N, 3d39'E) and
returned 7 August -
Commander David R. Scott,
Command module pilot Alfred M. Worden,
Lunar module pilot James B. Irwin.
The Rover travelled about 28km in total and
on the first excursion only the rear steering was operating.
Apollo 16 was launched on 16 April 1972, landed on the moon on 20 April (8d59'S, 15d31'E), and returned 27 April - Commander John W. Young, Command module pilot Thomas K. Mattingly II, Lunar module pilot Charles M. Duke jr.
Apollo 17 was launched on 7 December 1972, landed on the moon on 11 December (Taurus-Littrow 20d10'N, 30d46'E), and returned 19 December - Commander Eugene A. Cernan, Command module pilot Ronald E. Evans, Lunar module pilot Harrison H. Schmitt. The Rover (right) traversed about 35km in total.
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